The present invention relates generally to devices and methods for placing high pressure storage vessels into a vehicle structure, and more particularly to a way to integrate a vessel for storing a pressurized fuel source on a vehicle that employs a fuel cell-based architecture as a source of motive power such that the vessel increases the load-bearing capability of the vehicle.
In a typical fuel cell system, hydrogen or a hydrogen-rich gas is supplied through a flowpath to a catalytic electrode on one side of a fuel cell while oxygen (such as in the form of atmospheric oxygen) is supplied through a separate flowpath to another catalytic electrode situated elsewhere on the fuel cell. The electrochemical conversion of the elemental hydrogen and oxygen into hydrogen and oxygen ions on these electrodes (called anodes and cathodes, respectively) allows dissociated electrons to be routed through an electrically-conductive direct current (DC) circuit to produce useful work. One of the chief attributes of electric current production through fuel cells is their non-polluting nature, as the byproduct accompanying the use of hydrogen and oxygen reactants is water vapor. In one form of fuel cell, called the proton exchange membrane (PEM) fuel cell, an electrolyte in the form of a proton-transmissive membrane is sandwiched between the anode and cathode to produce a layered structure commonly referred to as a membrane electrode assembly (MEA). Each MEA forms a single fuel cell, and many such single cells can be combined to form a fuel cell stack, increasing the power output thereof. Multiple stacks can be coupled together to further increase power output. Because of its relatively simple and robust construction, as well as its non-polluting nature, the PEM fuel cell has shown particular promise for vehicular applications.
Nevertheless, one challenge for fuel cell vehicles is increasing their power-to-weight ratio relative to conventional propulsion systems, where much of the ancillary equipment weight associated with the fuel cell system is parasitic. One such component is the on-board fuel storage system, particularly as it relates to the hydrogen fuel storage tank, where its robustness and associated weight are dictated by the need to preserve tank integrity while containing a pressurized supply of hydrogen or related fuel (such as methanol or a hydrogen precursor) over the expected life of the vehicle, even in situations where both normal use (such as routine maneuvering and exposure to road irregularities) and extreme use (such as due to an accident or related impact) could otherwise damage the tank, vehicle or both. There accordingly exists a need to provide enhanced structural rigidity through the use of such components that are already present in a transportation vehicle. There further exists a need to reduce the penalties associated with placing a high pressure fuel storage vessel in a transportation vehicle.